Treatment of in vitro-Matured Bovine Oocytes With Tauroursodeoxycholic Acid Modulates the Oxidative Stress Signaling Pathway

Author(s)

Pioltine, Elisa Mariano ^[1] ; Costa, Camila Bortoliero ^[1] ; Barbosa Latorraca, Lais ^[2] ; Franchi, Fernanda Fagali ^[1] ; dos Santos, Priscila Helena ^[1] ; Mingoti, Gisele Zoccal ^[3] ; Paula-Lopes, Fabiola Freitas de ^[2] ; Nogueira, Marcelo Fabio Gouveia ^{[1, 4]}

Affiliation

^[1] Sao Paulo State Univ, Multiuser Lab Phytomed Pharmacol & Biotechnol Phi, Inst Biosci, Dept Pharmacol, Botucatu, SP - Brazil

^[2] Univ Fed Sao Paulo, Dept Biol Sci, Diadema - Brazil

^[3] Sao Paulo State Univ, Sch Vet Med, Dept Prod & Anim Hlth, Aracatuba - Brazil

^[4] Sao Paulo State Univ, Dept Biol Sci, Lab Embryon Micromanipulat, Sch Sci & Languages, Assis - Brazil

• Document type: Journal article
• Source: FRONTIERS IN CELL AND DEVELOPMENTAL BIOLOGY; v. 9, FEB 19 2021.
• Web of Science Citations: 0

Abstract

In several species, oocyte and embryo competence are improved by the addition of endoplasmic reticulum (ER) stress inhibitors to in vitro maturation (IVM) medium and/or in vitro culture (IVC) medium. This study aimed to evaluate the effects of three concentrations of tauroursodeoxycholic acid (TUDCA; 50, 200, and 1,000 mu M), a chemical chaperone for relieving ER stress, during IVM of bovine cumulus-oocyte complexes (COCs) for 24 h. Treated oocytes were analyzed for nuclear maturation, reactive oxygen species (ROS) production, mitochondrial activity, and abundance of target transcripts. In addition, the number of pronuclei in oocytes was evaluated after 18-20 h of insemination, and the rates of blastocyst and hatched blastocyst formation were evaluated after 7 and 8/9 days of culture, respectively. We further evaluated the transcript abundance of embryonic quality markers. Our findings showed that supplementation of IVM medium with 200 mu M of TUDCA decreased ROS production and increased abundance of transcripts related to antioxidant activity in oocytes (CAT, GPX1, and HMOX1) and embryos (GPX1 and PRDX3). Interestingly, high concentration of TUDCA (1,000 mu M) was toxic to oocytes, reducing the nuclear maturation rate, decreasing mitochondrial activity, and increasing the abundance of ER stress (HSPA5) and cellular apoptosis (CASP3 and CD40) related transcripts. The results of this study suggest that treatment with 200 mu M of TUDCA is associated with a greater resistance to oxidative stress and indirectly with ER stress relief in bovine oocytes. (AU)

• FAPESP's process: 12/50533-2 - GIFT: genomic improvement of fertilization traits in Danish and Brazilian cattle
• Grantee: Marcelo Fábio Gouveia Nogueira
• Support Opportunities: Research Projects - Thematic Grants